Engineering applications of Bragg-edge neutron transmission

The shape, magnitude and location of the Bragg edges appearing in the transmission spectrum of polycrystalline materials can be accurately determined by the time-of-flight technique, and hence information about the stress state, texture and phases present in the material is readily available. An advantage of Bragg-edge transmission over conventional neutron diffraction is that it can use a pixellated detector to map the strain in plane samples, producing images analogous to neutron radiography. Moreover, maps of the unstressed lattice spacing can be achieved by tilting the sample relative to the direction of the neutron beam. Examples of the application of this technique to typical engineering problems are presented in this work.